package com.example.hw_test;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TextView main_tv = findViewById(R.id.main_tv);
        main_tv.setText("测试");
    }
}
